Abstract: An activated carbon for adsorbing neutral per- and polyfluoroalkyl compounds used in quantitative analysis of neutral per- and polyfluoroalkyl compounds in a water sample includes an activated carbon having a BET specific surface area of 900 m2/g or more for desorbably adsorbing neutral per- and polyfluoroalkyl compounds distributed in a gas phase from the water sample by aerating or bubbling, with an inert gas as a carrier gas, the water sample sealed in a vessel and temperature-controlled to a temperature at which the neutral per- and polyfluoroalkyl compounds can be distributed in a gas phase.

Abstract: [SUMMARY] [OBJECT] To provide a per- and polyfluoroalkyl compound-adsorbing activated carbon having a high collection rate of per- and polyfluoroalkyl compounds in an atmospheric sample, and a filter body using the same. [ACHIEVING MEANS] A per- and polyfluoroalkyl compound-adsorbing activated carbon for desorbably adsorbing per- and polyfluoroalkyl compounds in an atmospheric sample, the activated carbon including an activated carbon adsorbent having a BET specific surface area of 900 m2/g or more, a sum (Vmic) of a volume of micropores of 1 nm or less of 0.35 cm3/g or more, a sum (Vmet) of a volume of mesopores of 2 to 60 nm of 0.02 cm3/g or more, a volume difference (Vs) between the micropore volume (Vmic) and the mesopore volume (Vmet) of 0.45 or more, and a surface oxide amount of 0.10 meq/g or more.

Abstract: [OBJECT] To provide an activated carbon for adsorbing per- and polyfluoroalkyl compounds in a water sample, the activated carbon having a high collection rate of per- and polyfluoroalkyl compounds in a water sample, and a filter body using the same. [ACHIEVING MEANS] An activated carbon for adsorbing per- and polyfluoroalkyl compounds in a water sample to desorbably adsorb per- and polyfluoroalkyl compounds in a water sample, wherein the activated carbon is composed of an activated carbon adsorbent having a BET specific surface area of 800 m2/g or more or a surface oxide amount of 0.20 meq/g or less, or alternatively, a BET specific surface area of 800 m2/g or more and a surface oxide amount of 0.50 meq/g or less, and wherein a sum (Vmic) of a volume of micropores of 1 nm or less of the activated carbon adsorbent is 0.30 cm3/g or more.

Abstract: The present invention provides a magnetic core part by which failures such as cracks do not occur even if the magnetic core part contains 90% by mass or more of an amorphous metal powder. The magnetic core part is formed by thermoset molding at least one magnetic powder selected from an amorphous metal powder alone and an amorphous metal powder coated with an insulating material, and a thermosetting binder resin. The magnetic core part contains the magnetic powder in an amount of 90% by mass or more and 99% by mass or less with respect to the total amount of the magnetic powder and the thermosetting binder resin.

Abstract: A shaft material integrally having a shaft portion and a flange portion is formed by a forging process. The end face of the shaft portion of the shaft material and the end face of the flange portion on the opposite side of the shaft portion are ground relative to the corrected face, and the outer circumferential surface of the shaft material is ground relative to the end faces. This renders the cylindricity of the radial bearing faces formed on the outer periphery of the shaft portion of the produced shaft member to be 3 ?m or lower. Moreover, a shaft material integrally having the shaft portion and flange portion is formed, while simultaneously thrust hydrodynamic groove regions are formed on both end faces of the flange portion. After the forging process, radial hydrodynamic groove regions are formed on the outer circumferential surface of the shaft portion.

Abstract: It is an object of the present invention to provide a bearing member having a highly accurate dynamic pressure generating portion stably at low cost. Dynamic pressure grooves (8a1) and (8a2) are formed as the dynamic pressure generating portions on an inner circumferential surface of the electroforming portion (10) by an electroforming process, and injection molding is performed by using a resin while inserting the electroforming portion (10), thereby forming a bearing member (8). A shaft member (2) is inserted into an inner circumference of the bearing member.

Abstract: A housing for a fluid lubrication bearing apparatus is produced. The housing has a cylindrical shape whose inner periphery having a fixing face to which an outer circumferential surface of a bearing sleeve is to be fixed. The method includes providing a forging mold having a groove molding portion extending parallel to a direction of a stroke of said mold and a face molding portion having a convex cylindrical shape on an outer periphery of the forging mold for forming the fixing face of the housing. The method further includes forming the housing with the forging mold, while forging circulation grooves and the fixing face simultaneously on the inner periphery of the housing with the groove molding portion and the face molding portion of the forging mold.

Abstract: A fluid bearing apparatus includes a housing 7 which has a cylindrical shape having a fixing face 7c for fixing the outer circumferential surface 8b of a bearing sleeve 8, and axial circulation grooves 7d for bringing both end faces 8c, 8d of the bearing sleeve 8 into circulation on the inner periphery by forging. A groove molding portion 18a2 is provided on the outer circumference of a rod 18 which serves as a forming mold for the inner periphery of the housing 7, and the circulation grooves 7d are formed by forging with this groove molding portion 18a2. Moreover, after a sealing face 107d and a cylindrical outer circumferential surface 107e provided on the outer periphery of the housing 107 are formed by forging, an inner circumferential surface 107c is formed by forging.

Abstract: A low-cost shaft member for hydrodynamic bearing apparatuses restores the pressure balance in a thrust bearing gap formed on both axial sides of the flange portion in an early stage. A shaft material integrally having a shaft portion and a flange portion with a through-hole between both end faces of the flange portion is formed in a common forging step. As a result, the through-hole is formed to open to an inner diameter side of the bearing gaps avoiding the thrust bearing gaps formed on both end faces of the flange portion of the shaft member as a finished product.

Abstract: An apparatus for manufacturing a hydro dynamic bearing device is provided for the finishing treatment of lubricating oil after lubricating the hydro dynamic bearing device, specifically for properly and effectively wiping off the lubricating oil adhering to the outside of the housing and adjusting the oil-level height of the lubricating oil filled in the housing.

Abstract: A method for producing a housing for a hydrodynamic bearing apparatus includes forming a housing 7 which has a cylindrical shape and which includes a fixing face 7c for fixing the outer circumferential surface 8b of a bearing sleeve 8, and axial circulation grooves 7d for bringing both end faces 8c, 8d of the bearing sleeve 8 into circulation on the inner periphery. The method includes providing a groove molding portion 18a2 on the outer circumference of a rod 18 which serves as a forming mold for the inner periphery of the housing 7, and forming the circulation grooves 7d of the housing by forging with the groove molding portion 18a2 of the mold. Moreover, after a sealing face 107d and a cylindrical outer circumferential surface 107e provided on the outer periphery of the housing 107 are formed by forging, an inner circumferential surface 107c is formed by forging.

Abstract: A method for producing a housing for a hydrodynamic bearing apparatus includes forming a housing 7 which has a cylindrical shape and which includes a fixing face 7c for fixing the outer circumferential surface 8b of a bearing sleeve 8, and axial circulation grooves 7d for bringing both end faces 8c, 8d of the bearing sleeve 8 into circulation on the inner periphery. The method includes providing a groove molding portion 18a2 on the outer circumference of a rod 18 which serves as a forming mold for the inner periphery of the housing 7, and forming the circulation grooves 7d of the housing by forging with the groove molding portion 18a2 of the mold. Moreover, after a sealing face 107d and a cylindrical outer circumferential surface 107e provided on the outer periphery of the housing 107 are formed by forging, an inner circumferential surface 107c is formed by forging.

Abstract: A low-cost shaft member for hydrodynamic bearing apparatuses restores the pressure balance in a thrust bearing gap formed on both axial sides of the flange portion in an early stage. A shaft material integrally having a shaft portion and a flange portion with a through-hole between both end faces of the flange portion is formed in a common forging step. As a result, the through-hole is formed to open to an inner diameter side of the bearing gaps avoiding the thrust bearing gaps formed on both end faces of the flange portion of the shaft member as a finished product.

Abstract: It is an object of the present invention to provide a bearing member having a highly accurate dynamic pressure generating portion stably at low cost. Dynamic pressure grooves (8a1) and (8a2) are formed as the dynamic pressure generating portions on an inner circumferential surface of the electroforming portion (10) by an electroforming process, and injection molding is performed by using a resin while inserting the electroforming portion (10), thereby forming a bearing member (8). A shaft member (2) is inserted into an inner circumference of the bearing member.

Abstract: To provide a fluid dynamic pressure bearing device that achieves high rigidity against moment without degradation in assembly precision and bearing performance, bearing sleeves are arranged in an axial direction and coaxiality of radial bearing surfaces formed on inner peripheral surfaces of the bearing sleeves is set to 3 ?m or less. This secures width precision between the radial bearing gaps to prevent a degradation in bearing performance and a failure such as wear etc. caused by contact between a shaft member and the bearing sleeves. Further, a first radial bearing surface and a second radial bearing surface are provided on at least one sleeve, and this allows a sleeve assembly constructed from the bearing sleeves to be supported at least three positions in the axial direction in a process of assembling the sleeve assembly.

Abstract: A fluid lubrication bearing apparatus which can stably produce high bearing performance is provided at low costs. Moreover, a method for producing a housing for hydrodynamic bearing apparatuses which can improve the accuracy of form of the housing of this type at low costs is provided. In forming a housing 7 which has a cylindrical shape and comprises a fixing face 7c for fixing the outer circumferential surface 8b of a bearing sleeve 8, and axial circulation grooves 7d for bringing both end faces 8c, Sd of the bearing sleeve 8 into circulation on the inner periphery by forging, a groove molding portion 18a2 is provided on the outer circumference of a rod 18 which serves as a forming mold for the inner periphery of the housing 7, and the circulation grooves 7d are formed by forging with this groove molding portion 18a2.

Abstract: An apparatus for manufacturing a hydro dynamic bearing device is provided for the finishing treatment of lubricating oil after lubricating the hydro dynamic bearing device, specifically for properly and effectively wiping off the lubricating oil adhering to the outside of the housing and adjusting the oil-level height of the lubricating oil filled in the housing.

Abstract: A shaft material integrally having a shaft portion and a flange portion is formed by a forging process. The end face of the shaft portion of the shaft material and the end face of the flange portion on the opposite side of the shaft portion are ground relative to the corrected face, and the outer circumferential surface of the shaft material is ground relative to the end faces. This renders the cylindricity of the radial bearing faces formed on the outer periphery of the shaft portion of the produced shaft member to be 3 ?m or lower. Moreover, a shaft material integrally having the shaft portion and flange portion is formed, while simultaneously thrust hydrodynamic groove regions are formed on both end faces of the flange portion. After the forging process, radial hydrodynamic groove regions are formed on the outer circumferential surface of the shaft portion.

Abstract: A method for manufacturing a hydro dynamic bearing device is provided for the finishing treatment of lubricating oil after lubricating the hydro dynamic bearing device, specifically for properly and effectively wiping off the lubricating oil adhering to the outside of the housing and adjusting the oil-level height of the lubricating oil filled in the housing.

Abstract: A low-cost shaft member for hydrodynamic bearing apparatuses restores the pressure balance in a thrust bearing gap formed on both axial sides of the flange portion in an early stage. A shaft material integrally having a shaft portion and a flange portion with a through-hole between both end faces of the flange portion is formed in a common forging step. As a result, the through-hole is formed to open to an inner diameter side of the bearing gaps avoiding the thrust bearing gaps formed on both end faces of the flange portion of the shaft member as a finished product.